Fig. 4: IL-2 treatment reduces the frequency of innate-like CD8⁺ MAIT and V_γ9V_δ2 T cells in circulation and selectively expands the IL-2 sensitive CD56^br NK cell subset.

a UMAP plot depicting the clustering of n = 93,379 unstimulated CD8⁺ T cells. Clusters were manually annotated based on the expression of key mRNA and protein markers. b Relative frequency changes of five selected CD8⁺ T cell clusters on Day 27 compared to the baseline (Day 0) levels, for unstimulated cells. c Relative frequency of the innate-like mucosal-associated invariant T cell (MAIT; left panel) and V_γ9V_δ2 T cell (right panel) clusters on Day 0, Day 27, and Day 55. Each line represents cells from a participant. Lines with the same colour represent the same participant. n = 13 participants. d UMAP plot depicting the clustering of n = 118,625 unstimulated NK cells. Clusters were manually annotated based on the expression of key mRNA and protein markers. e UMAP plot as in (d), split and coloured by FACS sorting gates of origin. f, g Relative frequency changes of five selected CD56^br (f) or CD56^dim (g) NK cell clusters on Day 27 compared to the baseline pre-treatment (Day 0) levels, for unstimulated cells. The relative frequency of each cluster is calculated as the number of cells in that cluster divided by the total number of cells sorted from the CD8 (b), CD56^br (f) or CD56^dim (g) NK cell gate. Each dot represents cells from a single participant. Dots with the same colour represent the same participant. n = 13 participants. Each box ranges from the first quartile (Q1) to the third quartile (Q3), with a central line indicating the median. The bottom and top whiskers extend to the most extreme data points within Q1 − 1.5 × (Q3 − Q1) and Q3 + 1.5 × (Q3 − Q1), respectively. P values were calculated using two-sided Wilcoxon signed-rank tests based on cell population frequencies between Day 27 and Day 0, followed by Benjamini–Hochberg FDR adjustment. Source data for (b, c, f, g) are provided as a Source Data file.